Risk assessment of lead and cadmium concentrations in hen's eggs using Monte Carlo simulations

The hen egg is one of the main sources of cheap, great quality, and nutritious food. This study aimed at determining the level of lead (Pb) and cadmium (Cd) in hen eggs and at assessing the carcinogenic and non-carcinogenic risks caused by the consumption of hen eggs collected in Iran. A total of 42 hen eggs from 17 major brands were randomly sampled from supermarkets. Lead and cadmium concentrations were determined by using inductively coupled plasma mass spectrometry (ICP-MS). Additionally, using the Monte Carlo simulation (MCS) method to calculate dietary exposure, target hazard quotient (THQ), and incremental lifetime cancer risk (ILCR), the related human health risk associated with ingesting these hazardous metals for adults was evaluated. The average Pb and Cd concentrations in whole eggs were 7.16 ± 0.248, and 2.83 ± 0.151 μg kg^-1, respectively, which were less than the maximum permitted levels, established by FAO/WHO and the Institute of Standards and Industrial Research of Iran (ISIRI). Pb and Cd concentrations were significantly correlated at the 0.05 level (r = 0.350). Regarding the levels of Pb and Cd in eggs, overall, the estimated weekly intake (EWI) of these metals for adults by egg consumption was determined 0.014 and 0.007 mg/week, respectively, which were lower than the risk values suggested. The carcinogenic and non-carcinogenic indexes of Cd and Pb indicated that the adult population in Iran was safe (THQ Pb and Cd <1, ILCR <10^-6 Pb). It should be emphasized that this research primarily focuses on egg consumption, which may account for a relatively small portion of Iranian consumers' overall exposure to Pb and Cd. Therefore, a comprehensive study on the risk assessment of these metals through whole-diet foods is recommended. The findings showed that lead and cadmium levels in all evaluated eggs were suitable for human consumption. Adults' Pb and Cd exposure from eating eggs was significantly lower than the risk levels established by Joint FAO/WHO Expert Committee on Food Additives (JECFA), per the exposure assessment. According to the THQ values of these dangerous metals, which were below one value, egg eating by Iranian consumers does not present a non-carcinogenic risk. In addition, this finding provides accurate and reliable information for policymakers to improve food safety status to reduce public health hazards.